In shock absorbers, there is a displacement response type shock absorber, including a bias spring configured to bias a disc valve to generate a damping force, configured to vary a spring force of the bias spring according to a position of a piston with respect to a cylinder and vary the damping force (for example, see Patent Literatures 1 and 2). In such a shock absorber, since a reaction force of the spring may be increased when the spring force of the bias spring is increased to increase the damping force, a degree of freedom in settings such as damping characteristics, a reaction force, or the like, in a design step is low.